The finest mac I know of is at Beaker and Flask. Along with having a great mix of sharp and softer cheeses, it comes with a massive slab of blood sausage on top. Excellent.
Agreed, this place is just okay. I'm not really a fan of breadcrumbs on my mac and cheese, but the combination of the weak sauce with overly bread-y flavor of the crumbs was a weird flavor fight in my mouth.